Afrostab--------Task's

Task 2 Questions
Question 1
Describe a computer network that you are familiar with. Provide an illustration of the network topology.
Our school uses a LAN network. The network topology of a LAN network is a star network.

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Question 2
What are the benefits of using a computer network?
You can share information, files, data and resources quickly and easily through a network. It is much easier to communicate via email and chat.
Question 3
What is the difference between a LAN and a WAN? Give an example of each.
A LAN network is a network that connects computers and devices in a small area like a home, school or business or in a local area.
A WAN network connects devices over a large area like a city, country or even the whole world. The internet is a good example of a WAN network.
Question 4:
The two main strategies for connecting computers are

Client/Server: A computer that retrieves information from and uses resources provided by a serveror main computer. Many corporate networks are comprised of a client computer at each of the employees' desks. Each of these computers connects to a central server or mainframe allowing the employees to work.

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Peer 2 Peer: A peer to peer network is a network that does not have a central computer or dedicated server,

in other words, all computers are independent.

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Question 5: The common network topologies used are ‘Star’, ‘Bus’ and ‘Ring’.

Star Topology: A star topology is one of the most common network setups where each of the devices and computers on a network connect to a central hub.

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Bus Topology: A type of network setup where each of the computers and network devices are connected to a single cable or backbone.

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Ring Topology: the ring topology is a type of computer network configuration where each network computer and device are connected to each other forming a large circle

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Question 6: There are many types of servers that can be connected to a network. Describe the purpose of each of the following:

File Server: Computer on a network that is used to provide users on a network with access to files.
Print Server: Computer responsible for managing one or more printers on a network.
Application Server: Server software that manages one or more other pieces of software in a way that makes the managed software available over a network, usually to a Web server

QUESTION 7
Computers connected to a network are required to have a network interface card (NIC). What is the purpose of a NIC?
The purpose of a Network Interface Card (NIC) is to provide your computer with a physical connection to a network. Almost all new computers come with a pre-installed NIC.

QUESTION 8

The following transmission media can be used to enable computers to communicate with each other.
· Twisted pair cable (shielded and unshielded)
· Coaxial cable
· Fibre optic
Describe each type of transmission media and provide an example of the situation in which it would best be used.

Twisted pair cable (shielded and unshielded)
A type of cable that consists of two independently insulated wires twisted around one another. The use of two wires twisted together helps to reduce crosstalk and electromagnetic induction.
Coaxial cable
A type of wire that consists of a center wire surrounded by insulation and then a grounded shield of braided wire. The shield minimizes electrical and radio frequency interference.

Fibre optic
Fibre optics use glass (or plastic) threads (fibers) to transmit data. A fiber optic cable consists of a bundle of glass threads, each of which is capable of transmitting messages modulated onto light waves.

QUESTION 9
In the area of data transmission, what do the following terms mean?
· Bandwidth
The amount of data that can be transmitted in a fixed amount of time.
· Baseband
A type of data transmission in which digital or analog data is sent over a single unmultiplexed channel
· Broadband
A type of data transmission in which a single medium (wire) can carry several channels at once.
· Simplex
Refers to transmission in only one direction.
· Half-duplex
Refers to the transmission of data in just one direction at a time. For example, a walkie-talkie is a half-duplex device because only one personcan talk at a time.
· Duplex
Refers to the transmission of data in two directions simultaneously. For example, a telephone is a full-duplex device because both people can talk at once.

QUESTION 10

What is the function of the following pieces of network hardware commonly used in LAN’s?
· Hub
A common connection point for devices in a network. Hubs are commonly used to connect segments of a LAN.
· Repeater
A network device used to regenerate or replicate a signal.
· Router
A device that forwards data packets along networks.
· Bridge
A device that connects two LAN's
· Gateway
A node on a network that serves as an entrance to another network.
· Switch
a device that filters and forwards packets between LAN segments

Question 11
What is the purpose of a network operating system (NOS)?
NOS is the software that organises, controls and coordinates the activities on a LAN network. It performs tasks such as administration, file management and security for the network.

Question 12
What are the most appropriate network operating systems for client/server and peer-to-peer networks?
The most appropriate network operating system is a LAN because it is easy and inexpensive.

Question 13
What are network protocols and why are they necessary?
A protocol is a set of rules and procedures for exchanging information between two computers. Transmission control protocol/Internet protocol (TCP/IP) is an example of a network protocol used primarily with the internet.